Calipers.



Patented 0st. I7, |899. J. H. SMITH. GALIPEHS.

(Application led May 17, 1899.)

No. 634,9la.

(Nu Modal.)

Unirse DnrArns PA'rnrrr @reina JAY HARLEY sinrri-i, on CHICO,CALIFORNIA.

CAMPERS.

SPECIFATIN forming part of Letters Patent No. 634,918, dated October1'7, 1899.

Application filed May 17, 1899. Serial No. 717,275. (No modell To @ZZwiz/0m it may concern:

Be it known that I, JAY HARLEY SMITH, a citizen of the United States,residing at Chico, in the County of Butte and State of California, haveinvented a new and useful Calipers, of which the following is aspeciiication.

My invention relates to calipers, and particularly to a device foraccurately locating the axle-centers on the tips of bicycle-forks, andalso adapted for use in other analogous relations where a relationbetween a vertical line and a horizontal line is required to beaccurately determined.

Further objects and advantages of this invention will appear in thefollowing description, and the novel features thereof will beparticularly pointed out in the appended claims, it being understoodthat the improvement is susceptible of various changes in the forni,proportion, size, and minor details of constructionwithout departingfromthe spirit or sacriiicing any of the advantages of the invention.

In the drawings, Figure 1 is a view of an instrument constructed inaccordance with my invention applied in the operative position of abicycle-fork to show the operation thereof, the axle-opening in one ofthe fork-tips having been bored and fitted With a removable plug, alsoforming a feature of my invention. Fig. 2 is a sectional view of thecalipers.

Similar reference characters indicate corresponding parts in both guresof the drawings.

The device embodying iny invention consists of a shank or body l, whichis preferably hollow to form a socket or guide 2, in which is fitted acenter pin 3 to engage the socket or opening in the crotch of abicycle-fork or analogous device, the upper end ofthe body having anannular central enlargementl concentric with the socket 2 and adapted topresent an effective bearing-surface to the edge of the opening in thecrotch of the fork-crown, in which it is adapted to be partiallyinserted. The pin 3 is secured in its adjusted positions by means of aset-screw 4. This shank or body portion of the instrument, in additionto its socket portion, embodies a flattened portion having alongitudinal slot 5, beyond which is arranged a pointer or indicator 6.Also connected with the shank are the caliper-legs 7 by means of a pivot8, having a clamping or set screw 9, and the free ends of said legs areprovided with outwardly-extending center points l0, adapted forindicating the marks at which the axle-centers are to be formed in thefork-tips.

In operation the center pin at the upper end of the shankor body portionof the instrument is inserted in the opening or socket at the crotch ofthe bicycle-fork, and the pointed extremities of the legs are separatedto occu py a position between the fork-tips and indicate the points ofthe axle-centers, the intermediate pointer or'indicator which isarranged between the legs serving as a medial line from which thedeflection of each leg from a vertical line may be measured, and hencethe accurate perpendicularity of a line connecting the points of thecaliper-legs with relation to a line connecting the extremity of thepointer and the axis of the center pin may be established.

It will be understood that while the device embodying my invention isparticularly designed and adapted for use in connection with determiningthe axle-centers of bicycles, it may be used with equal advantage inconnection with other operations requiring accuracy in analogousparticulars. After one of the axle openings or bearings has been formedin a forkstip a plug ll, as shown in Fig. l, may be fitted therein, saidplug having a center socket l2 for the reception of the point of one ofthe caliper-legs.

In practice after the plug is inserted the center pin 3 is entered inthe perforation in the crotch of the fork-crown and the enlarged head ofthe body is held tightly in engagement with the edge of the perforation.One of the caliper-legs is then adjusted with its outwardly-directedpoint in the socket 12 of the plug l1 and the other caliper-leg isydisposed with its outvvardly-directed point against the oppositefork-tip. The pointer 6 is adjusted to bisect the angle of thecaliperlegs, and in this adjustment of the pointer a pair of insidecalipers, a rule, or other measuring device may be employed, and Whenthe pointer is properly centered it Will be found that the points of thelegs lie in a line perpendicular to the line connecting the tip of thepointer and the center of adjustment of the legs, said legs being equalin length.

IOO

Having described my invention, what I claim isl. A caliper having ashank or bodyportion having an enlarged head and provided with aconcentric socket, a center pin fitted in said socket, a set-screw forsecuring the center pin at the desired adjustment, legs inounted forangular and longitudinal adjustment upon the shank or body portion, andmeans for securing said legs at the desired adjustment, substantially asspeciiied.

2. Acaliper having a shank or body having an enlarged head and providedwith a longitudinal socket concentric with the head, a pin adjustable inthe socket, a pointer or indicator extended longitudinally from the bodyportion and formed integral therewith, caliper-legs, a longitudinal slotin the body, and a clamping device engaging the slot of the body portionand pivotally connecting the legs therewith.

3. A caliper, having a body. portion provided with an enlarged head andhaving a longitudinal socket concentric with the head, a pin adjustablein the socket, a pointer or indicator extending longitudinally from thebody portion and formed integral therewith, caliper-legs, a longitudinalslot in the body, and a clamping device engaging the slot of the bodyportion and adjustably and pivotally connecting the legs therewith.

t. A caliper having a body portion provided with an enlarged head iixedthereto, a socket concentric with the head, a pin adjustable in thesocket, a screw adapted to clamp J AY HARLEY SMITH.

Witnesses:

J. D. MARGH, C. N. HOWARD.

